Although not so limited a typical application of the present invention is in commercial lawn service operations. Prior to the present invention an operator rendering a routine fertilizer treatment of a lawn would carry a separate spray gun for spot spraying patches of weeds and other undesirable vegetation. Obviously this is a cumbersome and time consuming operation.
While a herbicide could be mixed with the fertilizer this results in excessive use of herbicide in areas which did not require it. Additionally, an operator would not be sure that herbicide was actually being applied.